/**
 * Software License, Version 1.0
 * 
 * Copyright 2003 The Trustees of Indiana University.  All rights reserved.
 * 
 *
 *Redistribution and use in source and binary forms, with or without 
 *modification, are permitted provided that the following conditions are met:
 *
 *1) All redistributions of source code must retain the above copyright notice,
 * the list of authors in the original source code, this list of conditions and
 * the disclaimer listed in this license;
 *2) All redistributions in binary form must reproduce the above copyright 
 * notice, this list of conditions and the disclaimer listed in this license in
 * the documentation and/or other materials provided with the distribution;
 *3) Any documentation included with all redistributions must include the 
 * following acknowledgement:
 *
 *"This product includes software developed by the Community Grids Lab. For 
 * further information contact the Community Grids Lab at 
 * http://communitygrids.iu.edu/."
 *
 * Alternatively, this acknowledgement may appear in the software itself, and 
 * wherever such third-party acknowledgments normally appear.
 * 
 *4) The name Indiana University or Community Grids Lab or NaradaBrokering, 
 * shall not be used to endorse or promote products derived from this software 
 * without prior written permission from Indiana University.  For written 
 * permission, please contact the Advanced Research and Technology Institute 
 * ("ARTI") at 351 West 10th Street, Indianapolis, Indiana 46202.
 *5) Products derived from this software may not be called NaradaBrokering, 
 * nor may Indiana University or Community Grids Lab or NaradaBrokering appear
 * in their name, without prior written permission of ARTI.
 * 
 *
 * Indiana University provides no reassurances that the source code provided 
 * does not infringe the patent or any other intellectual property rights of 
 * any other entity.  Indiana University disclaims any liability to any 
 * recipient for claims brought by any other entity based on infringement of 
 * intellectual property rights or otherwise.  
 *
 *LICENSEE UNDERSTANDS THAT SOFTWARE IS PROVIDED "AS IS" FOR WHICH NO 
 *WARRANTIES AS TO CAPABILITIES OR ACCURACY ARE MADE. INDIANA UNIVERSITY GIVES
 *NO WARRANTIES AND MAKES NO REPRESENTATION THAT SOFTWARE IS FREE OF 
 *INFRINGEMENT OF THIRD PARTY PATENT, COPYRIGHT, OR OTHER PROPRIETARY RIGHTS. 
 *INDIANA UNIVERSITY MAKES NO WARRANTIES THAT SOFTWARE IS FREE FROM "BUGS", 
 *"VIRUSES", "TROJAN HORSES", "TRAP DOORS", "WORMS", OR OTHER HARMFUL CODE.  
 *LICENSEE ASSUMES THE ENTIRE RISK AS TO THE PERFORMANCE OF SOFTWARE AND/OR 
 *ASSOCIATED MATERIALS, AND TO THE PERFORMANCE AND VALIDITY OF INFORMATION 
 *GENERATED USING SOFTWARE.
 */
package cgl.narada.service.buffering;


/**
 * This thread is responsible for sorting the buffer and releasing the events in the buffer.
 * @author Hasan Bulut  - hbulut@indiana.edu
 */
public class BufferHandler extends Thread {
  //~ Instance fields ----------------------------------------------------------

  private BufferingServiceImpl buffServiceImpl;
  private Object               syncObj  = new Object();
  private boolean              running  = true;
  private long                 duration = 0;

  //~ Constructors -------------------------------------------------------------

  /**
   * Generates a new BufferHandler object.
   * @param buffServiceImpl - parent that initiates this thread
   */
  public BufferHandler(BufferingServiceImpl buffServiceImpl) {
    this.buffServiceImpl = buffServiceImpl;
    double rlsFactor = this.buffServiceImpl.getReleaseFactor();
    long   dur = this.buffServiceImpl.getBufferEntryMaximumDuration();
    duration = (long) Math.ceil(rlsFactor * dur);
    System.out.println("duration:" + rlsFactor + "\t" + dur + "\t" + duration);
    setName("BufferHandler");
  }

  //~ Methods ------------------------------------------------------------------

  /**
   * This thread can be notified by calling this method. On notification, this
   * thread sorts the buffer and releases the events in the buffer.
   */
  public void notifyBufferHandler() {
    synchronized (syncObj) {
      syncObj.notifyAll();
    }
  }

  /**
   * Waits on the buffering object. If release factor is set to 1.0, it releases
   * all of the events in the buffer by calling releaseAllEntries() method of
   * the parent. Otherwise it calls releaseAllEntries(double releaseFactor).
   * Thread wakes up if the waiting time is up, if the buffer is full and/or
   * maximum number of entries are reached and then notified.
   */
  public void run() {
    while (running) {
      this.waitOnBuffer();
      //      System.out.println("number of entries:"+this.buffServiceImpl.getTotalNumberOfEntries());
      if ((this.buffServiceImpl.getReleaseFactor() >= 1.0)) { // || ignoreReleaseFactor) {
        this.buffServiceImpl.releaseAllEntries();
      } else {
        this.buffServiceImpl.releaseAllEntries(this.buffServiceImpl.getReleaseFactor());
      }
    }
    this.buffServiceImpl.releaseAllEntries();
  }

  /**
   * Stops the running thread.
   */
  public void stopRunning() {
    running = false;
  }

  public void terminateService() {
    running = false;
    synchronized (syncObj) {
      syncObj.notify();
    }
  }

  /**
   * Calling this method causes the caller to wait on the synchronization object
   * for a maximum entry duration.
   */
  public void waitOnBuffer() {
    synchronized (syncObj) {
      try {
        syncObj.wait(duration);
      } catch (InterruptedException ex) {
      }
    }
  }

  /**
   * Calling this method causes the caller to wait on the synchronization object
   * for the time specified.
   */
  public void waitOnBuffer(long time) {
    synchronized (syncObj) {
      try {
        syncObj.wait(time);
      } catch (InterruptedException ex) {
      }
    }
  }
}
